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<title> Group ICA Toolbox Help </title>
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<h4> Detrending </h4>
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<p>
Detrending is used to remove the trend in the data by doing a line fit of 
nuisance parameters with the data. The order of detrend is determined by the 
nuisance parameters involved. GIFT uses four orders of detrend for removing the 
trend from the ICA time course. The nuisance parameters (X) for each order are 
shown below:</p>
<dl>
<dt> Order 0</dt>
<dd>X contains ones in first column.</dd>
<dd> </dd>
<dt> Order 1</dt>
<dd>X includes ramp function with mean removed in first column and ones in 
second column. </dd>
<dd> </dd>
<dt> Order 2</dt>
<dd>X includes sine one cycle in first column, cosine one cycle in second 
column, ramp function with mean removed in third column and ones in fourth 
column.</dd>
<dd> </dd>
<dt> Order 3</dt>
<dd>X includes sine two cycles in first column, cosine two cycles in second 
column, sine one cycle in third column, cosine one cycle in fourth column, ramp 
function with mean removed in fifth column and ones in sixth column.</dd>
</dl>
<p><b>Note:</b> The row length equals the data in all the orders.</p>
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